Potential wood burning insert install into heatilator fireplace

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eric_j

Member
Sep 25, 2019
18
Ny
I've learned quite a bit from reading this site, so thanks for all the education. We purchased a house a few years ago with this Heaterlator fireplace. Have not used it (much) and the smoke stains are pretty much what we inherited. Apologies for the quality of the photo, did not take it with the goal of posting. Its not cleared and I've obscured some photos, etc. The smoke staining cleaned up well with scrubbing and TSP. Now onto business

I would like to put in a wood burning insert. A visit by a very competent chimney sweep identified the flue as a 12x12 terra cotta liner and we had him do an estimate for a new fireplace. I think now an insert is the way to go. Plentiful supply of wood on the property, with space to season and natural accumulation of oak, maple and unfortunately ash (from EAB) that will supply wood. Goal is supplemental heating with some fire viewing. We are not there full time, but spending more time there, including a couple of months in the dead of winter. We are in the Hudson Valley, NY State. It is an outside chimney, about 15 feet tall. The area behind the masonry vents is open, presumably with the idea that warm air will will vent through.

I've explored different inserts, but before I ask anything about those, I'm more interested in the nature of the install.


1) The firebox is in rough shape, but can an insert simply be place into the liner as is? It sits in a very substantial and solid stone and morter structure that juts outside the house. Is this liner

2) I'm assuming we will need to do something with the hearth projecting into the room. The brick is currently 12 inches from the front of the firebox. This will depend on the requirements of the insert.


3) We will have to cut a hole through the rectangular slot, but I would guess that a 6 inch stainless steel liner that is insulated would be appropriate?

Thanks so much in advance. I'm most interested if just adding an insert seems like a viable strategy, and how constraining the size of the current firebox should be. Clearly we won't touch the stone dimensions, but the sloping side wall limit the kind of insert. I will have the install done professionally, but would appreciate very much independent opinions about how to proceed.
[Hearth.com] Potential wood burning insert install into heatilator fireplace
 
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How deep is the fireplace? How large an area will an insert be heating?
 
Sorry, didn't get included in the last image. I've uploaded another, zoomed into the firebox. It is 21 inches deep. width slopes from 30 inches to 22 in the back, and height starts at 26.5 inches and goes back straight to the start of the flue which is about 15 inches back. At the very end, the firebox is 13 inches tall, but it curves quickly upward. You can also see the condition of the firebox better.

The area to be depends upon ambition. Most important is the first floor, with a relatively open plan. A living room with the insert has a half wall opening to a dining room and kitchen, and a bedroom normally behind a closed door of probably a total of 900 sf. With ceiling fans it would be nice to get some heat up to a second floor set of rooms with another 800sf. The primary goal would be the downstairs though. Construction is mostly stone, and while the deed was from 1950, I believe the original building is much older than that.
Again, thanks for any insights.
[Hearth.com] Potential wood burning insert install into heatilator fireplace
 
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I’m not expert enough to get into all your questions but wanted to make the suggestion that you focus on researching non-flush inserts. Enviro, Lopi, Blaze King and I’m sure others have some that require less depth in the firebox because they put more on the hearth. Because you only have twelve inches out front as it stands, you’d most likely need to do something anyway. If you make a more substantial hearth, that gives you room to enjoy a non-flush Insert. Those will also be somewhat better at allowing radiant heat into the room, but you’d want a blower with any insert.
 
It's a big opening. A 2 cu ft insert would fit easily. That would cover the 900 sq ft. There are several. Is there a particular style that appeals?

How would the heat get upstairs? Where is the stairwell in relation to the stove room? Can you post a quick floorplan sketch?
 
It's a big opening. A 2 cu ft insert would fit easily. That would cover the 900 sq ft. There are several. Is there a particular style that appeals?

How would the heat get upstairs? Where is the stairwell in relation to the stove room? Can you post a quick floorplan sketch?

Thanks for both replies. I appreciate the fact that a non-flush insert would produce more heat, but aesthetics (particularly for my wife) are important. The Sirocco 25, with low 5 inch protusion is at the limit of acceptability. So as a general answer, what I believe is called a contemporary look is the goal.

For fit, I think the issue is the sloping sides of the fire box., If there is no need for clearance between the insert and the firebox, there is only 21 or 22 inches of width in the back. Inserts that are not tapered (like the Morso, Neo 2.5 etc) are a problem.

I'll post a sketch in a few minutes, but the exercise of drawing the space suggests that the upper levels would be stretch, even if the area has lots of fans...
 
How would the heat get upstairs? Where is the stairwell in relation to the stove room? Can you post a quick floorplan sketch?

It is hard to describe, but the 2nd floor sits on top of a master bedroom/entrance hallway and workshop, mechanicals and garage (not shown in diagram). Heat currently flows well upstairs, we seldom have the second zone of our oil fired burner on, and that area gets much less use. Stays @ 60-65 degrees on heat from downstairs until it gets into the single digits or teens.

So priority is sufficient hear for 1st floor, and then aesthetics which is fairly important. Pdf has a very rough floor plan
 

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Sorry, one other question. As you can see in the photo above, there is a lot of air space behind the vents for the ineffective heatilator. Any suggestions of how to deal with that? Should we insulate the space and replace the vents with the same local stone used to build the fireplace? I am hoping to get a insulated liner and block-off plate.
 
It is hard to describe, but the 2nd floor sits on top of a master bedroom/entrance hallway and workshop, mechanicals and garage (not shown in diagram). Heat currently flows well upstairs, we seldom have the second zone of our oil fired burner on, and that area gets much less use. Stays @ 60-65 degrees on heat from downstairs until it gets into the single digits or teens.

So priority is sufficient hear for 1st floor, and then aesthetics which is fairly important. Pdf has a very rough floor plan
Where are the stairs located on the first floor that go to the second floor? What is the approx. depth of the fireplace at 20"?
 
Stairway is at the opposite end of the first floor. Perhaps the attached makes the dimensions of the firebox clear. Does that answer your questions?
 

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Thanks, the PDF chopped up the drawing of the floors. Now I see where the stairs are.
A measurement of the depth at 20" from the hearth floor will help take the guess work out.
 
Not there now. Can get that mid week. I'm unsure exactly what you are asking in terms of measurements.....
Thanks. Is your concern a specific insert fitting?
 
Yes, most inserts are about 18-20" tall so the depth at that height is important. For example, if the depth at 18" is only 17" then you would need an insert no deeper than 17" unless the back metal was cut out.
 
Got it, thanks. Part of the reason I started this thread is to see if cutting out part of the metal there was a problem. Appreciate the clarification.
 
Have you looked at the small flush hybrid from Lopi? It looks like it would fit your space, five you the heat output and give your wife that flush look you’re looking for.
mom in the Hudson Valley as well. Have had two units installed by a local company (Firefox) that has done outstanding work. I have four neighbors who have also used them.
 
Thanks. Very much worth looking into. The local company is Firefox Energy in concepts in NJ? About an hour from this side of the river, but I'll reach out if those are the same folks.
 
Yes, they are in Lafayette, NJ. I’m about an hour away from them as well and they didn’t seem worried about the location.
 
Sorry, one other question. As you can see in the photo above, there is a lot of air space behind the vents for the ineffective heatilator. Any suggestions of how to deal with that? Should we insulate the space and replace the vents with the same local stone used to build the fireplace? I am hoping to get a insulated liner and block-off plate.
I had a 1950 Era heatilator with rusted out back panels that I covered with thin steel sheets. I stuffed roxul in the vent holes and covered openings with metal fabricated covers that were painted black to match insert surround. I notched the damper with a plasma cutter and filled the area around it with roxul as well. I made a block off plate from sheet steel and glued about 8 inches of roxul to the top to insulate it. I heat a small cape with a fpx flush insert. If I had the option I would of ripped out fireplace and put a free standing stove. NOT SURE WHAT YOUR SITUATION IS.
I insulated my liner and ordered an upgraded chimney cap and plate. Putting the liner in with my dad in January on snow covered staging planks at night was a nightmare to say the least . I have a small 1600 ft cape that I heat no problem. Downstairs will be about 74-77 degrees and upstairs about 68- 70. Wood needs to be dry and split for at least 18 months in my opinion to operate insert properly and get burn times and proper btu output.
 
Thanks for the tips, EBFire. I Your plan makes a lot of sense then, and certainly will insulate the liner. Were your able to get enough Roxul in to insulate the area? How large were the areas you filled? Did it seem to insulate enough?
Wood has seasoned for two summers from a standing dead maple, and another two cords of oak, ash and a little birch are split and under cover. Come cherry to follow from standing dead.
As you can see, it and the chimney extend outward from the room, but heating that massive stone structure is not my goal. That's why I'm interested in insulating the area outside the insert. A freestanding stove is not in the cards I'm afraid.
rt.[Hearth.com] Potential wood burning insert install into heatilator fireplace
 
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Thanks for the tips, EBFire. I Your plan makes a lot of sense then, and certainly will insulate the liner. Were your able to get enough Roxul in to insulate the area? How large were the areas you filled? Did it seem to insulate enough?
Wood has seasoned for two summers from a standing dead maple, and another two cords of oak, ash and a little birch are split and under cover. Come cherry to follow from standing dead.
As you can see, it and the chimney extend outward from the room, but heating that massive stone structure is not my goal. That's why I'm interested in insulating the area outside the insert. A freestanding stove is not in the cards I'm afraid.
rt.View attachment 249850
My chimney is partially outside my home and I felt the insulation of the heatilatir vents and smoke chamber and block off plate were sufficient. Covering the heatilator vents with matching stone would look the best . Or you could put a fancy tile or other material to break up the natural stone look and add color. Regarding the vents Just stuff as much roxul in there as possible and close them up . Some people insulate behind the insert with roxul but I think it’s a bad idea . Just be cautious if you cut the heatilator steel liner it’s insulated with either asbestos or another white colored insulation that I can’t think of the correct name . Something wool ??? I covered my steel with new steel instead of creating a mess. An insert that has more surface area into the living space uses less fan and is much better in power outages . Without a fan my flush insert is useless . Without a generator to power my fan for my insert I have no heat . Things to think about . I bought a batt of roxul from Lowe’s and I only used about 1/4 to insulate everything I needed to. The smoke shelf area needs the most in my application . I didn’t look into how much chimney was needed for my insert I just got lucky so do your homework on that aspect .
 
Just measured. the back of the firebox tilts in slowly from a height of about 13 inches. Hard to measure exactly, but 20 inches high touches the sloping back plate at about 18.5 inches. I think many inserts would require a cutoff so the liner could attach to the insert, but I'm no expert. But some cutting to run the liner is not uncommon, is it? It is very close for many inserts.

Been advised that a Blaze King Sirocco 25 will fit, and it has the wife's approval. Will extend the hearth. Does that seem reasonable?

Installer will provide an insulated block-off plate, but am wondering if an insulated liner wi a worthwhile add on at $450

Thanks, and suggestions welcome.
 
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In my opinion the insulated liner is the most important. Make up cardboard templates to make sure stove dimensions will fit. Also the angle of the liner entering through damper area is also important so everything lines up.
 
Just measured. the back of the firebox tilts in slowly from a height of about 13 inches. Hard to measure exactly, but 20 inches high touches the sloping back plate at about 18.5 inches. I think many inserts would require a cutoff so the liner could attach to the insert, but I'm no expert. But some cutting to run the liner is not uncommon, is it? It is very close for many inserts.

Been advised that a Blaze King Sirocco 25 will fit, and it has the wife's approval. Will extend the hearth. Does that seem reasonable?

Installer will provide an insulated block-off plate, but am wondering if an insulated liner wi a worthwhile add on at $450

Thanks, and suggestions welcome.
Insulation on the liner should not be an add on. It is almost always required for code compliance. And the performance gains are well worth it
 
Just thought I would post during and an 'after' image. Install went well, installer correctly removed the old tiles, replaced with an insulated liner, filled the heatolator vents, etc. No doubt will be back with questions, but the Sirocco 25 seems great. Will clean up a little (moulding on the hearth, hide the electrical cord, but I wanted to thank all for the advice and input.

First question: The fan rheostat seems to go very low, but the fan is not off. Is that correct? [edit: You turn the fan off by going past the fastest setting, not the slowest]
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